Pyrolysis of waste plastics in a film reactor

Patent metadata

Field	Value
Publication number	US-2023139587-A1
Application number	US-202117995713-A
Country	US
Kind code	A1
Filing date	Apr 13, 2021
Priority date	Apr 13, 2020
Publication date	May 4, 2023
Grant date	—

Abstract

A process and system for liquefying and plasticizing a waste plastic in a pyrolysis film reactor are provided. More particularly, a liquefied waste plastic, which may include halogen-depleted molten waste plastics, may be pyrolyzed in a pyrolysis film reactor to form a pyrolysis oil and a pyrolysis gas. The pyrolysis film reactors may include a falling film reactor and/or an upflow film reactor.

First claim

What is claimed is:

1 . A chemical recycling process comprising:
(a) providing a liquefied waste plastic; (b) introducing at least a portion of said liquefied waste plastic into an upflow pyrolysis film reactor comprising a plurality of stationary film-generating structures; and (c) flowing at least a portion of said liquefied waste plastic upwardly along said stationary film-generating structures to thereby pyrolyze said liquefied waste plastic and form a pyrolysis effluent comprising a pyrolysis gas.

2 . The process according to claim 1 , wherein said stationary film-generating structures comprise tubes, wires, plates, rings, saddles, sheets, grids, screens, nets, or combinations thereof.

3 . The process according to claim 2 , wherein said liquefied waste plastic has a residence time in said upflow pyrolysis film reactor of 2 to 300 seconds.

4 . The process according to claim 3 , wherein said upflow pyrolysis film reactor operates at a temperature of 450° C. to 1,100° C.

5 . The process according to claim 1 , wherein said providing of step (a) comprises liquefying at least one solid waste plastic in a melt tank to form said liquefied waste plastic.

6 . The process according to claim 5 , wherein said liquefying occurs in the presence of at one dissolution solvent.

7 . The process according to claim 6 , wherein said dissolution solvent comprises a pyrolysis oil.

8 . The process according to claim 7 , wherein said pyrolysis oil is derived from said pyrolysis effluent.

9 . The process of any of claims 5 through 8 , wherein said solid waste plastic comprises at least 90 weight percent of one or more polyolefins.

10 . The process of any of claims 5 through 8 , wherein said solid waste plastic comprises not more than 3 weight percent of PET, PVC, or a combination thereof.

11 . The process of any of claims 1 through 8 , wherein said liquefied waste plastic has a viscosity of less than 3,000 poise at 350° C. and 10 radians/s.

12 . The process of any of claims 1 through 8 , wherein said liquefied waste plastic has a halogen content of not more than 100 ppmw.

13 . A chemical recycling process comprising:
(a) liquefying at least one solid waste plastic to form a liquefied waste plastic having a viscosity of less than 800 poise at 350° C. and 10 radians/s; (b) introducing at least a portion of said liquefied waste plastic into a pyrolysis film reactor; and (c) converting at least a portion of said liquefied waste plastic in said pyrolysis film reactor into a pyrolysis effluent comprising a pyrolysis gas.

14 . The process of according to claim 13 , wherein said liquefied waste plastic has a residence time in said pyrolysis film reactor of 2 to 300 seconds, wherein said pyrolysis film reactor operates at a temperature of 450° C. to 1,100° C.

15 . The process according to claim 13 , wherein said liquefying comprises liquefying said solid waste plastic in a melt tank to form said liquefied waste plastic.

16 . The process according to claim 15 , wherein said liquefying occurs in the presence of at one dissolution solvent.

17 . The process according to claim 16 , wherein said dissolution solvent comprises a pyrolysis oil.

18 . The process according to claim 17 , wherein said pyrolysis oil is derived from said pyrolysis effluent.

19 . The process according to claim 13 , wherein said solid waste plastic comprises at least 90 weight percent of one or more polyolefins, wherein said solid waste plastic comprises not more than 3 weight percent of PET, PVC, or a combination thereof.

20 . A chemical recycling process comprising:
(a) separating a solid waste plastic feed into a polyolefin-enriched stream and a polyolefin-depleted stream; (b) liquefying said polyolefin-enriched stream to thereby provide a liquefied waste plastic; (c) introducing at least a portion of said liquefied waste plastic into a pyrolysis film reactor; and (d) converting at least a portion of said liquefied waste plastic in said pyrolysis film reactor into a pyrolysis effluent comprising a pyrolysis gas.

21 . The process of according to claim 20 , wherein said liquefied waste plastic has a residence time in said pyrolysis film reactor of 2 to 300 seconds, wherein said pyrolysis film reactor operates at a temperature of 450° C. to 1,100° C.

22 . The process according to claim 20 , wherein said liquefying comprises liquefying said solid waste plastic in a melt tank to form said liquefied waste plastic.

23 . The process according to claim 22 , wherein said liquefying occurs in the presence of at one dissolution solvent.

24 . The process according to claim 23 , wherein said dissolution solvent comprises a pyrolysis oil.

25 . The process according to claim 24 , wherein said pyrolysis oil is derived from said pyrolysis effluent.

26 . The process according to claim 20 , wherein said solid waste plastic feed comprises at least 90 weight percent of one or more polyolefins, wherein said solid waste plastic comprises not more than 3 weight percent of PET, PVC, or a combination thereof.

27 . A chemical recycling process comprising:
(a) liquefying at least one solid waste plastic in the presence of a dissolution solvent to form a liquefied waste plastic, wherein said dissolution solvent comprises a pyrolysis oil; (b) introducing at least a portion of said liquefied waste plastic into a pyrolysis film reactor; and (c) converting at least a portion of said liquefied waste plastic in said pyrolysis film reactor into a pyrolysis effluent comprising a pyrolysis gas.

28 . The process of according to claim 27 , wherein said liquefied waste plastic has a residence time in said pyrolysis film reactor of 2 to 300 seconds, wherein said pyrolysis film reactor operates at a temperature of 450° C. to 1,100° C.

29 . The process according to claim 27 , wherein said liquefying comprises liquefying said solid waste plastic in a melt tank to form said liquefied waste plastic.

30 . The process according to claim 27 , wherein said pyrolysis oil is derived from said pyrolysis effluent.

31 . The process according to claim 27 , wherein said solid waste plastic feed comprises at least 90 weight percent of one or more polyolefins, wherein said solid waste plastic comprises not more than 3 weight percent of PET, PVC, or a combination thereof.

32 . The process of any of claims 13 through 31 , wherein said pyrolysis film reactor comprises a falling film reactor, a wiped film reactor, a structured packing reactor, a screen reactor, a parallel wires reactor, a vacuum film reactor, a perforated plate reactor, an upflow tubular reactor, or a combination thereof.

33 . The process of any of claims 13 through 31 , wherein said pyrolysis film reactor comprises a falling film reactor.

34 . The process of any of claims 13 through 31 , wherein said pyrolysis film reactor comprises an upflow film reactor.

35 . The process of any of claims 13 through 31 , wherein said liquefied waste plastic has a viscosity of less than 500 poise at 350° C. and 10 radians/s.

36 . The process of any of claims 13 through 31 , wherein said liquefied waste plastic has a halogen content of not more than 100 ppmw.

37 . A che

Assignees

• Eastman Chem Co

Inventors

• Debruin Bruce Roger
• Bitting Daryl
• Slivensky David Eugene
• Wu Xianchun
• Ekart Michael Paul
• Lange David Milton
• Edens Aaron Nathanial

Classifications

• C10G1/10

  from rubber or rubber waste · CPC title

• C08J2323/00

  Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers · CPC title

• C08J11/12

  by dry-heat treatment only · CPC title

• C10J3/66 Primary

  by introducing them into the gasification zone · CPC title

• C10J3/00

  Production of combustible gases containing carbon monoxide from solid carbonaceous fuels (destructive distillation processes C10B) · CPC title